Carbon capture and sequestration (CCS) is a key consideration of any system or method that produces carbon dioxide (CO2). This is particularly relevant to power production through combustion of a fossil fuel or other hydrocarbon-containing material. Several power production methods have been suggested where CCS is achievable. One publication in the field of high efficiency power generation with CCS, U.S. Pat. No. 8,596,075 to Allam et al., provides for desirable efficiencies in closed cycle oxy-fuel combustion systems utilizing a recycle CO2 stream. In such system, the CO2 is captured as a relatively pure stream at high pressure.
Current proposals for CO2 disposal often require transportation in high pressure pipelines as a high density, supercritical fluid at pressures of 100 bar (10 MPa) to 250 bar (25 MPa). Such pipelines require high capital expenditures. Piped CO2 is either sequestered in an underground geologic formation, such as a deep saline aquifer, or may be used to economic advantage, such as for enhanced oil recovery (EOR).
The use of CO2 for EOR necessitates its availability over a wide area of an oil rich region. This would require the extensive use of a network of pipelines extending over the region. This becomes prohibitively expensive in many uses, particularly off-shore oil fields. It thus would be useful to provide bulk quantities of CO2 (such as produced from a power production system and method) in liquid form that would be easier for delivery to off-shore oil production platforms. Other beneficial uses of CO2 gathered from power production facilities can be envisioned if the CO2 could be provided in a liquefied form.